1. Field of the Invention
The present invention generally relates to an image processing apparatus and an image forming apparatus, and more particularly, to an image processing apparatus that forms an image in which a plurality of component images are composited (formed into a composite image), an image forming apparatus in which the image processing apparatus is provided, a computer program that causes a computer to function as the image processing apparatus, and a computer readable recording medium storing the computer program.
2. Description of the Related Art
JPEG is one of the most widely used image compression/decompression algorithms. JPEG 2000, a successive technique to JPEG, is a further improved algorithm that offers higher performance and various additional functions. JPEG 2000 is expected to become the de facto standard of the next generation that realizes superfine compression/decompression of still pictures.
Recent improvements in the precision of image forming apparatuses have enabled one to composite a plurality of pages into fewer pages. The rapid growth in information available through computers as well as concerns about environmental problems increase demand for such compositing of pages.
Conventionally, each image is decompressed, expanded in a memory, and shrunk to a certain size, if necessary.
The conventional technique of compositing images, however, requires much more time and memory space than processing of single images does. Users need to prepare more memory capacity and spend more time to process the compositing of images than to process the images as they are.
To solve such problems, Japanese Patent
Laid-open Application No. 2000-156829 discloses an invention to save memory capacity by processing the compositing of images by lines or alternative small units.
Japanese Patent Laid-open Application No. 2000-156830 discloses an invention in which an additional buffer is provided so as to accelerate the compositing of images.
Additionally, Japanese Patent Laid-open
Application No. 2001-148774 discloses an invention in which users can designate the number of images to be composited.
Japanese Patent Laid-open Application No. 10-322542 discloses an invention for the compositing of previously composited images.
The inventions disclosed in the above first and second references, however, cannot solve the problem that each image to be composited is expanded in the memory one by one, taking much more time than processing of single images.
Neither of the inventions disclosed in the above third and fourth references is the solution to the problem.